Complex Sortal Predicates
We define a formal language for sortals with a lambda operator. By means of this language, a formal representation of the logical structure of complex sortal concepts and complex sortal predicates is possible. A formal semantics for the language is also defined together with a formal system. The system is proved to be complete and sound with respect to the semantics. Both the system and the semantics do not have commitments regarding which lambda abstracts will stand for sortal concepts. The possibility of comprehension schemata for this sort of postulational commitments is discussed at the end of the chapter.